学习使用php实现生成模糊图片的方法类整理

<?php

class image_blur
{
    
    

    /**
     * 图片高斯模糊（适用于png/jpg/gif格式）
     * @param $srcImg 原图片
     * @param $savepath 保存路径
     * @param $savename 保存名字
     * @param $positon 模糊程度
     * @blurFactor的值代表模糊程度
     *基于Martijn Frazer代码的扩充， 感谢 Martijn Frazer
     */

    public function gaussian_blur($srcImg, $savepath = null, $savename = null, $blurFactor = 3)
    {
    
    

        $gdImageResource = $this->image_create_from_ext($srcImg);

        $srcImgObj = $this->blur($gdImageResource, $blurFactor);

        $temp = pathinfo($srcImg);

        $name = $temp['basename'];

        $path = $temp['dirname'];

        $exte = $temp['extension'];

        $savename = $savename ? $savename : $name;

        $savepath = $savepath ? $savepath : $path;

        $savefile = $savepath . '/' . $savename;

        $srcinfo = @getimagesize($srcImg);

        switch ($srcinfo[2]) {
    
    

            case 1:
                imagegif($srcImgObj, $savefile);
                break;

            case 2:
                imagejpeg($srcImgObj, $savefile);
                break;

            case 3:
                imagepng($srcImgObj, $savefile);
                break;

            default:
                return '保存失败'; //保存失败

        }

        return $savefile;

        imagedestroy($srcImgObj);

    }

    /**
     * Strong Blur
     *
     * @param $gdImageResource 图片资源
     * @param $blurFactor 可选择的模糊程度
     * 可选择的模糊程度 0使用 3默认 超过5时 极其模糊
     * @return GD image 图片资源类型
     * @author Martijn Frazer, idea based on http://stackoverflow.com/a/20264482
     */

    private function blur($gdImageResource, $blurFactor = 3)

    {
    
    

// blurFactor has to be an integer

        $blurFactor = round($blurFactor);

        $originalWidth = imagesx($gdImageResource);

        $originalHeight = imagesy($gdImageResource);

        $smallestWidth = ceil($originalWidth * pow(0.5, $blurFactor));

        $smallestHeight = ceil($originalHeight * pow(0.5, $blurFactor));

// for the first run, the previous image is the original input

        $prevImage = $gdImageResource;

        $prevWidth = $originalWidth;

        $prevHeight = $originalHeight;

// scale way down and gradually scale back up, blurring all the way

        for ($i = 0; $i < $blurFactor; $i += 1) {
    
    

// determine dimensions of next image

            $nextWidth = $smallestWidth * pow(2, $i);

            $nextHeight = $smallestHeight * pow(2, $i);

// resize previous image to next size

            $nextImage = imagecreatetruecolor($nextWidth, $nextHeight);

            imagecopyresized($nextImage, $prevImage, 0, 0, 0, 0,

                $nextWidth, $nextHeight, $prevWidth, $prevHeight);

// apply blur filter

            imagefilter($nextImage, IMG_FILTER_GAUSSIAN_BLUR);

// now the new image becomes the previous image for the next step

            $prevImage = $nextImage;

            $prevWidth = $nextWidth;

            $prevHeight = $nextHeight;

        }

// scale back to original size and blur one more time

        imagecopyresized($gdImageResource, $nextImage,

            0, 0, 0, 0, $originalWidth, $originalHeight, $nextWidth, $nextHeight);

        imagefilter($gdImageResource, IMG_FILTER_GAUSSIAN_BLUR);

// clean up

        imagedestroy($prevImage);

// return result

        return $gdImageResource;

    }

    private function image_create_from_ext($imgfile)

    {
    
    

        $info = getimagesize($imgfile);

        $im = null;

        switch ($info[2]) {
    
    

            case 1:
                $im = imagecreatefromgif($imgfile);
                break;

            case 2:
                $im = imagecreatefromjpeg($imgfile);
                break;

            case 3:
                $im = imagecreatefrompng($imgfile);
                break;

        }

        return $im;

    }

}

$image_blur = new image_blur();

$image_blur->gaussian_blur("./wenku_pic.jpg", null, 'wenku_pic_mohu.jpg', 3);

?>

原图效果：

生成模糊图片后的效果：